c/8395: gcc 2.95.4 and 3.2 generate wrong code for double on intel

[Bruce Allen]

The following reply was made to PR c/8395; it has been noted by GNATS.

From: Bruce Allen <ballen@gravity.phys.uwm.edu>
To: Marco Bernardo <bernardo@sti.uniurb.it>
Cc: Bruce Allen <ballen@aei.mpg.de>, gcc-gnats@gcc.gnu.org,
       gcc-prs@gcc.gnu.org, gcc-bugs@gcc.gnu.org, nobody@gcc.gnu.org
Subject: Re: c/8395: gcc 2.95.4 and 3.2 generate wrong code for double on
 intel
Date: Mon, 4 Nov 2002 04:58:02 -0600 (CST)

 > 2. I hope we all agree on the fact that the output produced by
 >    a (sequential) C program is the same for a given input,
 >    regardless of the compilation options that are used.
 
 Absolutely false!
 
 C does not specify the order in which mathematical expressions are
 evaluated, unless the programmer makes these completely explicity.
 
 And indeed compiling with optimizations turned on can eliminate many
 subexpressions, cause compile-time evaluatiosn, register sorage etc, which
 can also change results.
 
 Bruce Allen